~bzr-pqm/bzr/bzr.dev

# Copyright (C) 2010, 2011 Canonical Ltd

#

# This program is free software; you can redistribute it and/or modify

# it under the terms of the GNU General Public License as published by

# the Free Software Foundation; either version 2 of the License, or

# (at your option) any later version.

#

# This program is distributed in the hope that it will be useful,

# but WITHOUT ANY WARRANTY; without even the implied warranty of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

# GNU General Public License for more details.

#

# You should have received a copy of the GNU General Public License

# along with this program; if not, write to the Free Software

# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

"""ControlDir is the basic control directory class.

The ControlDir class is the base for the control directory used

by all bzr and foreign formats. For the ".bzr" implementation,

see bzrlib.bzrdir.BzrDir.

"""

from bzrlib.lazy_import import lazy_import

lazy_import(globals(), """

import textwrap

from bzrlib import (

    errors,

    hooks,

    revision as _mod_revision,

    transport as _mod_transport,

    trace,

    ui,

    urlutils,

    )

from bzrlib.transport import local

from bzrlib.push import (

    PushResult,

    )

from bzrlib.i18n import gettext

""")

from bzrlib import registry

class ControlComponent(object):

    """Abstract base class for control directory components.

    This provides interfaces that are common across controldirs,

    repositories, branches, and workingtree control directories.

    They all expose two urls and transports: the *user* URL is the

    one that stops above the control directory (eg .bzr) and that

    should normally be used in messages, and the *control* URL is

    under that in eg .bzr/checkout and is used to read the control

    files.

    This can be used as a mixin and is intended to fit with

    foreign formats.

    """

    @property

    def control_transport(self):

        raise NotImplementedError

    @property

    def control_url(self):

        return self.control_transport.base

    @property

    def user_transport(self):

        raise NotImplementedError

    @property

    def user_url(self):

        return self.user_transport.base

class ControlDir(ControlComponent):

    """A control directory.

    While this represents a generic control directory, there are a few

    features that are present in this interface that are currently only

    supported by one of its implementations, BzrDir.

    These features (bound branches, stacked branches) are currently only

    supported by Bazaar, but could be supported by other version control

    systems as well. Implementations are required to raise the appropriate

    exceptions when an operation is requested that is not supported.

    This also makes life easier for API users who can rely on the

    implementation always allowing a particular feature to be requested but

    raising an exception when it is not supported, rather than requiring the

    API users to check for magic attributes to see what features are supported.

    """

    def can_convert_format(self):

        """Return true if this controldir is one whose format we can convert

        from."""

        return True

    def list_branches(self):

        """Return a sequence of all branches local to this control directory.

        """

        try:

            return [self.open_branch()]

        except (errors.NotBranchError, errors.NoRepositoryPresent):

            return []

    def is_control_filename(self, filename):

        """True if filename is the name of a path which is reserved for

        controldirs.

        :param filename: A filename within the root transport of this

            controldir.

        This is true IF and ONLY IF the filename is part of the namespace reserved

        for bzr control dirs. Currently this is the '.bzr' directory in the root

        of the root_transport. it is expected that plugins will need to extend

        this in the future - for instance to make bzr talk with svn working

        trees.

        """

        raise NotImplementedError(self.is_control_filename)

    def needs_format_conversion(self, format=None):

        """Return true if this controldir needs convert_format run on it.

        For instance, if the repository format is out of date but the

        branch and working tree are not, this should return True.

        :param format: Optional parameter indicating a specific desired

                       format we plan to arrive at.

        """

        raise NotImplementedError(self.needs_format_conversion)

    def create_repository(self, shared=False):

        """Create a new repository in this control directory.

        :param shared: If a shared repository should be created

        :return: The newly created repository

        """

        raise NotImplementedError(self.create_repository)

    def destroy_repository(self):

        """Destroy the repository in this ControlDir."""

        raise NotImplementedError(self.destroy_repository)

    def create_branch(self, name=None, repository=None,

                      append_revisions_only=None):

        """Create a branch in this ControlDir.

        :param name: Name of the colocated branch to create, None for

            the default branch.

        :param append_revisions_only: Whether this branch should only allow

            appending new revisions to its history.

        The controldirs format will control what branch format is created.

        For more control see BranchFormatXX.create(a_controldir).

        """

        raise NotImplementedError(self.create_branch)

    def destroy_branch(self, name=None):

        """Destroy a branch in this ControlDir.

        :param name: Name of the branch to destroy, None for the default 

            branch.

        """

        raise NotImplementedError(self.destroy_branch)

    def create_workingtree(self, revision_id=None, from_branch=None,

        accelerator_tree=None, hardlink=False):

        """Create a working tree at this ControlDir.

        :param revision_id: create it as of this revision id.

        :param from_branch: override controldir branch 

            (for lightweight checkouts)

        :param accelerator_tree: A tree which can be used for retrieving file

            contents more quickly than the revision tree, i.e. a workingtree.

            The revision tree will be used for cases where accelerator_tree's

            content is different.

        """

        raise NotImplementedError(self.create_workingtree)

    def destroy_workingtree(self):

        """Destroy the working tree at this ControlDir.

        Formats that do not support this may raise UnsupportedOperation.

        """

        raise NotImplementedError(self.destroy_workingtree)

    def destroy_workingtree_metadata(self):

        """Destroy the control files for the working tree at this ControlDir.

        The contents of working tree files are not affected.

        Formats that do not support this may raise UnsupportedOperation.

        """

        raise NotImplementedError(self.destroy_workingtree_metadata)

    def find_branch_format(self, name=None):

        """Find the branch 'format' for this controldir.

        This might be a synthetic object for e.g. RemoteBranch and SVN.

        """

        raise NotImplementedError(self.find_branch_format)

    def get_branch_reference(self, name=None):

        """Return the referenced URL for the branch in this controldir.

        :param name: Optional colocated branch name

        :raises NotBranchError: If there is no Branch.

        :raises NoColocatedBranchSupport: If a branch name was specified

            but colocated branches are not supported.

        :return: The URL the branch in this controldir references if it is a

            reference branch, or None for regular branches.

        """

        if name is not None:

            raise errors.NoColocatedBranchSupport(self)

        return None

    def open_branch(self, name=None, unsupported=False,

                    ignore_fallbacks=False):

        """Open the branch object at this ControlDir if one is present.

        If unsupported is True, then no longer supported branch formats can

        still be opened.

        TODO: static convenience version of this?

        """

        raise NotImplementedError(self.open_branch)

    def open_repository(self, _unsupported=False):

        """Open the repository object at this ControlDir if one is present.

        This will not follow the Branch object pointer - it's strictly a direct

        open facility. Most client code should use open_branch().repository to

        get at a repository.

        :param _unsupported: a private parameter, not part of the api.

        TODO: static convenience version of this?

        """

        raise NotImplementedError(self.open_repository)

    def find_repository(self):

        """Find the repository that should be used.

        This does not require a branch as we use it to find the repo for

        new branches as well as to hook existing branches up to their

        repository.

        """

        raise NotImplementedError(self.find_repository)

    def open_workingtree(self, _unsupported=False,

                         recommend_upgrade=True, from_branch=None):

        """Open the workingtree object at this ControlDir if one is present.

        :param recommend_upgrade: Optional keyword parameter, when True (the

            default), emit through the ui module a recommendation that the user

            upgrade the working tree when the workingtree being opened is old

            (but still fully supported).

        :param from_branch: override controldir branch (for lightweight

            checkouts)

        """

        raise NotImplementedError(self.open_workingtree)

    def has_branch(self, name=None):

        """Tell if this controldir contains a branch.

        Note: if you're going to open the branch, you should just go ahead

        and try, and not ask permission first.  (This method just opens the

        branch and discards it, and that's somewhat expensive.)

        """

        try:

            self.open_branch(name)

            return True

        except errors.NotBranchError:

            return False

    def _get_selected_branch(self):

        """Return the name of the branch selected by the user.

        :return: Name of the branch selected by the user, or None.

        """

        branch = self.root_transport.get_segment_parameters().get("branch")

        if branch is not None:

            branch = urlutils.unescape(branch)

        return branch

    def has_workingtree(self):

        """Tell if this controldir contains a working tree.

        This will still raise an exception if the controldir has a workingtree

        that is remote & inaccessible.

        Note: if you're going to open the working tree, you should just go ahead

        and try, and not ask permission first.  (This method just opens the

        workingtree and discards it, and that's somewhat expensive.)

        """

        try:

            self.open_workingtree(recommend_upgrade=False)

            return True

        except errors.NoWorkingTree:

            return False

    def cloning_metadir(self, require_stacking=False):

        """Produce a metadir suitable for cloning or sprouting with.

        These operations may produce workingtrees (yes, even though they're

        "cloning" something that doesn't have a tree), so a viable workingtree

        format must be selected.

        :require_stacking: If True, non-stackable formats will be upgraded

            to similar stackable formats.

        :returns: a ControlDirFormat with all component formats either set

            appropriately or set to None if that component should not be

            created.

        """

        raise NotImplementedError(self.cloning_metadir)

    def checkout_metadir(self):

        """Produce a metadir suitable for checkouts of this controldir."""

        return self.cloning_metadir()

    def sprout(self, url, revision_id=None, force_new_repo=False,

               recurse='down', possible_transports=None,

               accelerator_tree=None, hardlink=False, stacked=False,

               source_branch=None, create_tree_if_local=True):

        """Create a copy of this controldir prepared for use as a new line of

        development.

        If url's last component does not exist, it will be created.

        Attributes related to the identity of the source branch like

        branch nickname will be cleaned, a working tree is created

        whether one existed before or not; and a local branch is always

        created.

        :param revision_id: if revision_id is not None, then the clone

            operation may tune itself to download less data.

        :param accelerator_tree: A tree which can be used for retrieving file

            contents more quickly than the revision tree, i.e. a workingtree.

            The revision tree will be used for cases where accelerator_tree's

            content is different.

        :param hardlink: If true, hard-link files from accelerator_tree,

            where possible.

        :param stacked: If true, create a stacked branch referring to the

            location of this control directory.

        :param create_tree_if_local: If true, a working-tree will be created

            when working locally.

        """

        raise NotImplementedError(self.sprout)

    def push_branch(self, source, revision_id=None, overwrite=False, 

        remember=False, create_prefix=False):

        """Push the source branch into this ControlDir."""

        br_to = None

        # If we can open a branch, use its direct repository, otherwise see

        # if there is a repository without a branch.

        try:

            br_to = self.open_branch()

        except errors.NotBranchError:

            # Didn't find a branch, can we find a repository?

            repository_to = self.find_repository()

        else:

            # Found a branch, so we must have found a repository

            repository_to = br_to.repository

        push_result = PushResult()

        push_result.source_branch = source

        if br_to is None:

            # We have a repository but no branch, copy the revisions, and then

            # create a branch.

            if revision_id is None:

                # No revision supplied by the user, default to the branch

                # revision

                revision_id = source.last_revision()

            repository_to.fetch(source.repository, revision_id=revision_id)

            br_to = source.clone(self, revision_id=revision_id)

            if source.get_push_location() is None or remember:

                source.set_push_location(br_to.base)

            push_result.stacked_on = None

            push_result.branch_push_result = None

            push_result.old_revno = None

            push_result.old_revid = _mod_revision.NULL_REVISION

            push_result.target_branch = br_to

            push_result.master_branch = None

            push_result.workingtree_updated = False

        else:

            # We have successfully opened the branch, remember if necessary:

            if source.get_push_location() is None or remember:

                source.set_push_location(br_to.base)

            try:

                tree_to = self.open_workingtree()

            except errors.NotLocalUrl:

                push_result.branch_push_result = source.push(br_to, 

                    overwrite, stop_revision=revision_id)

                push_result.workingtree_updated = False

            except errors.NoWorkingTree:

                push_result.branch_push_result = source.push(br_to,

                    overwrite, stop_revision=revision_id)

                push_result.workingtree_updated = None # Not applicable

            else:

                tree_to.lock_write()

                try:

                    push_result.branch_push_result = source.push(

                        tree_to.branch, overwrite, stop_revision=revision_id)

                    tree_to.update()

                finally:

                    tree_to.unlock()

                push_result.workingtree_updated = True

            push_result.old_revno = push_result.branch_push_result.old_revno

            push_result.old_revid = push_result.branch_push_result.old_revid

            push_result.target_branch = \

                push_result.branch_push_result.target_branch

        return push_result

    def _get_tree_branch(self, name=None):

        """Return the branch and tree, if any, for this controldir.

        :param name: Name of colocated branch to open.

        Return None for tree if not present or inaccessible.

        Raise NotBranchError if no branch is present.

        :return: (tree, branch)

        """

        try:

            tree = self.open_workingtree()

        except (errors.NoWorkingTree, errors.NotLocalUrl):

            tree = None

            branch = self.open_branch(name=name)

        else:

            if name is not None:

                branch = self.open_branch(name=name)

            else:

                branch = tree.branch

        return tree, branch

    def get_config(self):

        """Get configuration for this ControlDir."""

        raise NotImplementedError(self.get_config)

    def check_conversion_target(self, target_format):

        """Check that a controldir as a whole can be converted to a new format."""

        raise NotImplementedError(self.check_conversion_target)

    def clone(self, url, revision_id=None, force_new_repo=False,

              preserve_stacking=False):

        """Clone this controldir and its contents to url verbatim.

        :param url: The url create the clone at.  If url's last component does

            not exist, it will be created.

        :param revision_id: The tip revision-id to use for any branch or

            working tree.  If not None, then the clone operation may tune

            itself to download less data.

        :param force_new_repo: Do not use a shared repository for the target

                               even if one is available.

        :param preserve_stacking: When cloning a stacked branch, stack the

            new branch on top of the other branch's stacked-on branch.

        """

        return self.clone_on_transport(_mod_transport.get_transport(url),

                                       revision_id=revision_id,

                                       force_new_repo=force_new_repo,

                                       preserve_stacking=preserve_stacking)

    def clone_on_transport(self, transport, revision_id=None,

        force_new_repo=False, preserve_stacking=False, stacked_on=None,

        create_prefix=False, use_existing_dir=True, no_tree=False):

        """Clone this controldir and its contents to transport verbatim.

        :param transport: The transport for the location to produce the clone

            at.  If the target directory does not exist, it will be created.

        :param revision_id: The tip revision-id to use for any branch or

            working tree.  If not None, then the clone operation may tune

            itself to download less data.

        :param force_new_repo: Do not use a shared repository for the target,

                               even if one is available.

        :param preserve_stacking: When cloning a stacked branch, stack the

            new branch on top of the other branch's stacked-on branch.

        :param create_prefix: Create any missing directories leading up to

            to_transport.

        :param use_existing_dir: Use an existing directory if one exists.

        :param no_tree: If set to true prevents creation of a working tree.

        """

        raise NotImplementedError(self.clone_on_transport)

    @classmethod

    def find_bzrdirs(klass, transport, evaluate=None, list_current=None):

        """Find control dirs recursively from current location.

        This is intended primarily as a building block for more sophisticated

        functionality, like finding trees under a directory, or finding

        branches that use a given repository.

        :param evaluate: An optional callable that yields recurse, value,

            where recurse controls whether this controldir is recursed into

            and value is the value to yield.  By default, all bzrdirs

            are recursed into, and the return value is the controldir.

        :param list_current: if supplied, use this function to list the current

            directory, instead of Transport.list_dir

        :return: a generator of found bzrdirs, or whatever evaluate returns.

        """

        if list_current is None:

            def list_current(transport):

                return transport.list_dir('')

        if evaluate is None:

            def evaluate(controldir):

                return True, controldir

        pending = [transport]

        while len(pending) > 0:

            current_transport = pending.pop()

            recurse = True

            try:

                controldir = klass.open_from_transport(current_transport)

            except (errors.NotBranchError, errors.PermissionDenied):

                pass

            else:

                recurse, value = evaluate(controldir)

                yield value

            try:

                subdirs = list_current(current_transport)

            except (errors.NoSuchFile, errors.PermissionDenied):

                continue

            if recurse:

                for subdir in sorted(subdirs, reverse=True):

                    pending.append(current_transport.clone(subdir))

    @classmethod

    def find_branches(klass, transport):

        """Find all branches under a transport.

        This will find all branches below the transport, including branches

        inside other branches.  Where possible, it will use

        Repository.find_branches.

        To list all the branches that use a particular Repository, see

        Repository.find_branches

        """

        def evaluate(controldir):

            try:

                repository = controldir.open_repository()

            except errors.NoRepositoryPresent:

                pass

            else:

                return False, ([], repository)

            return True, (controldir.list_branches(), None)

        ret = []

        for branches, repo in klass.find_bzrdirs(

                transport, evaluate=evaluate):

            if repo is not None:

                ret.extend(repo.find_branches())

            if branches is not None:

                ret.extend(branches)

        return ret

    @classmethod

    def create_branch_and_repo(klass, base, force_new_repo=False, format=None):

        """Create a new ControlDir, Branch and Repository at the url 'base'.

        This will use the current default ControlDirFormat unless one is

        specified, and use whatever

        repository format that that uses via controldir.create_branch and

        create_repository. If a shared repository is available that is used

        preferentially.

        The created Branch object is returned.

        :param base: The URL to create the branch at.

        :param force_new_repo: If True a new repository is always created.

        :param format: If supplied, the format of branch to create.  If not

            supplied, the default is used.

        """

        controldir = klass.create(base, format)

        controldir._find_or_create_repository(force_new_repo)

        return controldir.create_branch()

    @classmethod

    def create_branch_convenience(klass, base, force_new_repo=False,

                                  force_new_tree=None, format=None,

                                  possible_transports=None):

        """Create a new ControlDir, Branch and Repository at the url 'base'.

        This is a convenience function - it will use an existing repository

        if possible, can be told explicitly whether to create a working tree or

        not.

        This will use the current default ControlDirFormat unless one is

        specified, and use whatever

        repository format that that uses via ControlDir.create_branch and

        create_repository. If a shared repository is available that is used

        preferentially. Whatever repository is used, its tree creation policy

        is followed.

        The created Branch object is returned.

        If a working tree cannot be made due to base not being a file:// url,

        no error is raised unless force_new_tree is True, in which case no

        data is created on disk and NotLocalUrl is raised.

        :param base: The URL to create the branch at.

        :param force_new_repo: If True a new repository is always created.

        :param force_new_tree: If True or False force creation of a tree or

                               prevent such creation respectively.

        :param format: Override for the controldir format to create.

        :param possible_transports: An optional reusable transports list.

        """

        if force_new_tree:

            # check for non local urls

            t = _mod_transport.get_transport(base, possible_transports)

            if not isinstance(t, local.LocalTransport):

                raise errors.NotLocalUrl(base)

        controldir = klass.create(base, format, possible_transports)

        repo = controldir._find_or_create_repository(force_new_repo)

        result = controldir.create_branch()

        if force_new_tree or (repo.make_working_trees() and

                              force_new_tree is None):

            try:

                controldir.create_workingtree()

            except errors.NotLocalUrl:

                pass

        return result

    @classmethod

    def create_standalone_workingtree(klass, base, format=None):

        """Create a new ControlDir, WorkingTree, Branch and Repository at 'base'.

        'base' must be a local path or a file:// url.

        This will use the current default ControlDirFormat unless one is

        specified, and use whatever

        repository format that that uses for bzrdirformat.create_workingtree,

        create_branch and create_repository.

        :param format: Override for the controldir format to create.

        :return: The WorkingTree object.

        """

        t = _mod_transport.get_transport(base)

        if not isinstance(t, local.LocalTransport):

            raise errors.NotLocalUrl(base)

        controldir = klass.create_branch_and_repo(base,

                                               force_new_repo=True,

                                               format=format).bzrdir

        return controldir.create_workingtree()

    @classmethod

    def open_unsupported(klass, base):

        """Open a branch which is not supported."""

        return klass.open(base, _unsupported=True)

    @classmethod

    def open(klass, base, _unsupported=False, possible_transports=None):

        """Open an existing controldir, rooted at 'base' (url).

        :param _unsupported: a private parameter to the ControlDir class.

        """

        t = _mod_transport.get_transport(base, possible_transports)

        return klass.open_from_transport(t, _unsupported=_unsupported)

    @classmethod

    def open_from_transport(klass, transport, _unsupported=False,

                            _server_formats=True):

        """Open a controldir within a particular directory.

        :param transport: Transport containing the controldir.

        :param _unsupported: private.

        """

        for hook in klass.hooks['pre_open']:

            hook(transport)

        # Keep initial base since 'transport' may be modified while following

        # the redirections.

        base = transport.base

        def find_format(transport):

            return transport, ControlDirFormat.find_format(

                transport, _server_formats=_server_formats)

        def redirected(transport, e, redirection_notice):

            redirected_transport = transport._redirected_to(e.source, e.target)

            if redirected_transport is None:

                raise errors.NotBranchError(base)

            trace.note(gettext('{0} is{1} redirected to {2}').format(

                 transport.base, e.permanently, redirected_transport.base))

            return redirected_transport

        try:

            transport, format = _mod_transport.do_catching_redirections(

                find_format, transport, redirected)

        except errors.TooManyRedirections:

            raise errors.NotBranchError(base)

        format.check_support_status(_unsupported)

        return format.open(transport, _found=True)

    @classmethod

    def open_containing(klass, url, possible_transports=None):

        """Open an existing branch which contains url.

        :param url: url to search from.

        See open_containing_from_transport for more detail.

        """

        transport = _mod_transport.get_transport(url, possible_transports)

        return klass.open_containing_from_transport(transport)

    @classmethod

    def open_containing_from_transport(klass, a_transport):

        """Open an existing branch which contains a_transport.base.

        This probes for a branch at a_transport, and searches upwards from there.

        Basically we keep looking up until we find the control directory or

        run into the root.  If there isn't one, raises NotBranchError.

        If there is one and it is either an unrecognised format or an unsupported

        format, UnknownFormatError or UnsupportedFormatError are raised.

        If there is one, it is returned, along with the unused portion of url.

        :return: The ControlDir that contains the path, and a Unicode path

                for the rest of the URL.

        """

        # this gets the normalised url back. I.e. '.' -> the full path.

        url = a_transport.base

        while True:

            try:

                result = klass.open_from_transport(a_transport)

                return result, urlutils.unescape(a_transport.relpath(url))

            except errors.NotBranchError, e:

                pass

            try:

                new_t = a_transport.clone('..')

            except errors.InvalidURLJoin:

                # reached the root, whatever that may be

                raise errors.NotBranchError(path=url)

            if new_t.base == a_transport.base:

                # reached the root, whatever that may be

                raise errors.NotBranchError(path=url)

            a_transport = new_t

    @classmethod

    def open_tree_or_branch(klass, location):

        """Return the branch and working tree at a location.

        If there is no tree at the location, tree will be None.

        If there is no branch at the location, an exception will be

        raised

        :return: (tree, branch)

        """

        controldir = klass.open(location)

        return controldir._get_tree_branch()

    @classmethod

    def open_containing_tree_or_branch(klass, location):

        """Return the branch and working tree contained by a location.

        Returns (tree, branch, relpath).

        If there is no tree at containing the location, tree will be None.

        If there is no branch containing the location, an exception will be

        raised

        relpath is the portion of the path that is contained by the branch.

        """

        controldir, relpath = klass.open_containing(location)

        tree, branch = controldir._get_tree_branch()

        return tree, branch, relpath

    @classmethod

    def open_containing_tree_branch_or_repository(klass, location):

        """Return the working tree, branch and repo contained by a location.

        Returns (tree, branch, repository, relpath).

        If there is no tree containing the location, tree will be None.

        If there is no branch containing the location, branch will be None.

        If there is no repository containing the location, repository will be

        None.

        relpath is the portion of the path that is contained by the innermost

        ControlDir.

        If no tree, branch or repository is found, a NotBranchError is raised.

        """

        controldir, relpath = klass.open_containing(location)

        try:

            tree, branch = controldir._get_tree_branch()

        except errors.NotBranchError:

            try:

                repo = controldir.find_repository()

                return None, None, repo, relpath